1. Field of the Invention
The present invention relates to a feedthrough capacitor arrangement, and more particularly to a feedthrough capacitor arrangement for use in a high frequency apparatus such as an electronic tuner for a television receiver, particularly a CATV converter.
2. Description of the Prior Art
FIG. 16 is a sectional view showing a mounting arrangement for a conventional feedthrough capacitor which is in the background of the present invention. A shield frame 10 is provided with a round hole 12 with printed circuit boards 14 and 16 disposed in the vicinity thereof. A feedthrough capacitor 18 is inserted in the round hole 12 of the shield frame 10, and its outer electrode 20 is soldered to the shield frame 10 and both ends 22a and 22b of its central electrode 22 are soldered to the printed circuit boards 14 and 16 respectively.
Two methods are employable for mounting such a feedthrough capacitor 18.
In a first method, the feedthrough capacitor 18 is inserted in the round hole 12 of the shield frame 10 as shown in FIG. 17 and fitted with a solder ring 24 as shown in FIG. 18. Then, heat is applied from, e.g., an oven, to effect soldering as shown in FIG. 19. Then the printed circuit boards 14 and 16 are assembled in the shield frame 10 and then the central electrode of the feedthrough capacitor 18 is soldered to conductor patterns on the printed circuit boards 14 and 16 respectively.
In a second method, the frame 10 and the printed circuit boards 14 and 16 are assembled and then the feedthrough capacitor 18 is inserted in the round hole 12 of the frame 10 as shown in FIGS. 20 and 21. Thereafter the outer electrode 20 is soldered to the shield frame 10, and both ends 22a and 22b of the central electrode 22 of the feedthrough capacitor 18 are soldered to the printed circuit boards 14 and 16 respectively by solder dipping.
In the aforementioned first method, the feedthrough capacitor 18 is first soldered to the frame 10 and then to the printed circuit boards 14 and 16 by separate steps. If another feedthrough capacitor is to be employed in a different direction, further, the same cannot be assembled with the aforementioned feedthrough capacitor 18. In the first method, thus, mounting of the feedthrough capacitor 18 is complicated.
On the other hand, the second method is inferior in fitting workability since the available space around the round hole 12 is restricted by the printed circuit boards 14 and 16 which are assembled in a structure which includes the shield frame 10 before insertion of the feedthrough capacitor 18. Further, the feedthrough capacitor 18 may be displaced from the shield frame 10 by loosening of the solder in the subsequent solder dipping steps, whereby soldering correction is required in a later step. Thus, the second method is inferior in workability.